جامع الترمذي

Narrated Ibn 'Abbas: "The Quraish said to the Jews: 'Give us something that we can ask this man about.' So he said: 'Ask him about the Ruh.' So they asked him about the Ruh. So Allah Most High, revealed: They ask you concerning the Ruh. Say: The Ruh is one of the things, the knowledge of which is only with my Lord. And of knowledge, you have been given only a little (17:85). They replied: 'We have been given immense knowledge, we were given the Tawrah, and whoever has been given the Tawrah, then he has indeed been given a wealth of knowledge.' So the following was revealed: Say: 'If the sea were ink for the Words of my Lord, surely the sea would be exhausted (before the Words of my Lord would be finished.) (18:109)'"